The 30 circuit is direct to the battery and the 87 is direct to the fuel pump, so connecting them will start the pump. The WUR heater works off the 15 (ignition on) circuit, so jumping the 30 and 87 will not heat the WUR. The control pressure can be tested without heating the WUR. If the engine is cold, just use the ambient temp to compare your test results. You test the heater by taking an ohm reading between the two connects and testing each connect for a fault to ground.

The haynes manual was probably referring to the pump running for a few seconds when the key is turned to on and the relay installed. This primes the fuel system.

Understand about testing the heater, but there in lies an assumption that if the hearter works the warm control pressure will be on spec.

SO my question is if i do in fact wish to test the warm control pressure how do i accomplish this.

also Idola you mention about pulling the injectors. I know all of mine are fine, do i really need to pull them. Since the fuel pressure tests are performed with the engine off, the air sensor plate and arm should be down and therefore no fuel being injected into the intake. And i know none of mine leak when the sensor plate is at rest._________________TheBib

Yes, if the cold control pressure is correct and the heating element is working correctly, the warm control pressure should be within spec also. If you want to test it warm, run the engine, measure the temp of the body of the WUR and compare the control pressure to the chart at that temp.

You would only want to pull the injectors if the system failed the leakdown test.

Another question Ideola, when you mention connection of the lines, I understand the press guage test line without the valve goes to the fuel distributor.

However is the pressure guage test line with the valve connected to the very line that you removed from the fuel distributor? (in other words all i am doing is putting the test appratus inbetween the fuel distributor and the line i removed from the fuel distributor. Or do you mean i need to trace back the WUR line back and single out that single line alone. Reason i ask is if i trace the line from the WUR on its merry way to the fuel distributor, it tees off multiple times._________________TheBib

Dan -- in my previous post hopefully the pictures show up. If not let me know and I'll try to re-post. By the way, where I mention WUV I actually meant to say WUR. I'm going to try to work on it tomorrow._________________TheBib

I'm setting my WUR at the moment, but I see there's no mention of the control pressure during boost (M31.01 Euro).
Does anyone have the boost control pressure value?
This way I can set the boost control pressure by moving the disk at the bottom of the wur.

This is a multiple connection Tee branch that the WUV line connects through on its way to the WUV

Line connected to the WUV

5 years later I had exactly the same question. And I found the solution: you need to connect the meter directly to the fuel distributor. So it will be positioned between the fuel distributor and the valve._________________924 - 1982
911SC - 1980